We're trying to fix the uneven floors in our 850 sqft, 80 year-old house in San Jose. Our contractor opened up the floors and the problem appears to be that the floor joists rest on a skid, while the rim joist rests on the foundation, and there's ~1" difference between the surface of the skid and the surface of the foundation. See photo below.
Any ideas on the right way to level the rim joist with the floor joists? How expensive would you expect a good solution to be? Is inserting shims around the rim joist an option? (I think that would require jacking up the wall...)
Thank you for your thoughts!